Intracytoplasmic sperm injection (ICSI) in unexplained and stage I endometriosis-associated infertility after fertilization failure with in vitro fertilization (IVF)

Purpose: To investigate possible differences between unexplained and stage I endometriosis-associated infertility in ICSI cycles conducted after low fertilization (<20%) in preceding IVF cycles with normal semen parameters. Methods: Retrospective cohort study consisting of patients with unexplained (n=48) and stage I endometriosis-associated infertility (n=43) with a minimum of one IVF cycle with <20% fertilized oocytes and normal semen quality, treated with ICSI from January 1997 to January 2006. Age matched male factor infertility patients (n=91) were used as controls. Results: Diploid fertilization rate was significantly lower in the stage I endometriosis-associated infertility group compared to the unexplained infertility group. Score of the transferred embryos, implantation rate, pregnancy rate and outcome were similar in the two groups. Conclusions: ICSI appears to be an efficient treatment option after fertilization failure with IVF in unexplained and stage I endometriosis-associated infertility.